Fetal Endotracheal Occlusion (FETO) in Severe and Extremely Severe Congenital Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) occurs when the diaphragm fails to fully fuse and leaves a portal through which abdominal structures can migrate into the thorax. In the more severe cases, the abdominal structures remain in the thoracic cavity and compromise the development of the lungs. Infants born with this defect have a decreased capacity for gas exchange; mortality rates after birth have been reported between 40-60%. Now that CDH can be accurately diagnosed by mid-gestation, a number of strategies have been developed to repair the hernia and promote lung tissue development. Fetal tracheal occlusion is one technique that temporarily closes the herniated area with the Goldvalve balloon to allow the lungs to develop and increase survival at birth. This is a pilot study of a cohort of fetuses affected by severe CDH that will undergo FETO to demonstrate the feasibility of performing the procedure, managing the pregnancy during the period of tracheal occlusion, and removal of the device prior to delivery at BCM/Texas Children's Hospital (TCH). It is anticipated that fetal tracheal occlusion plug-unplug procedure will improve mortality and morbidity outcomes as compared with current management, but this is not a primary endpoint of the feasibility study. We will perform 20 FETO procedures on fetuses diagnosed prenatally with severe and extremely severe CDH.

INCLUSION CRITERIA: * Patient is a pregnant woman between 18 and 45 years of age * Singleton pregnancy * Confirmed diagnosis of severe or extremely severe left, right or bilateral CDH of the fetus Severe CDH: -Fetal liver herniated into the hemithorax -Lung-head ratio (LHR) is less than or equal to 1.0 calculated between 27+0/7 and 29+6/7 weeks' gestation Extremely Severe CDH: -At least 1/3rd of the liver parenchyma herniated into the thoracic cavity -Lung-head ratio (LHR) is \< 0.71 calculated between 22+0/7 and 29+6/7 weeks' gestation * Normal fetal echocardiogram or echocardiogram with a minor anomaly (such a small VSD) that in the opinion of the pediatric cardiologist will not affect postnatal outcome * Normal fetal karyotype * The mother must be healthy enough to have surgery * Patient provides signed informed consent that details the maternal and fetal risks involved with the procedure * Patient willing to remain in Houston for the duration following the balloon placement until delivery * Signed informed consent EXCLUSION CRITERIA: * Contraindication to abdominal surgery, fetoscopic surgery, or general anesthesia * Allergy to latex * Allergy or previous adverse reaction to a study medication specified in this protocol * Preterm labor, preeclampsia, or uterine anomaly (e.g., large fibroid tumor) * Fetal aneuploidy, known structural genomic variants, other major fetal anomalies, or known syndromic mutation * Suspicion of major recognized syndrome (e.g. Fryns syndrome) on ultrasound or MRI * Maternal BMI \>40 * High risk for fetal hemophilia